Spin-exchange relaxation of naturally abundant Rb in a K–Rb–<sup>21</sup>Ne self-compensated atomic comagnetometer

Spin-exchange relaxation of naturally abundant Rb in a K–Rb–²¹Ne self-compensated atomic comagnetometer

Lu Yan¹, Zhai Yueyang^{2, 3, 4}, Zhang Yong¹, Fan Wenfeng¹, Xing Li¹, Quan Wei^{2, 3, 4, †}

Intuitive model of the operation principle: (a) Rb and ²¹Ne achieve polarization equilibrium, then the comagnetometer is set to the self-compensated state with B_z = −B2^c = −(Bⁿ + B^e); (b) when there is a rotation rate input Ω_y, the Rb electron spins are quickly repolarized, while the ²¹Ne nuclear spins remain oriented with respect to an inertial frame; (c) under the torque of magnetic field B_z on ²¹Ne nuclear spins, Pⁿ and, accordingly, Bⁿ rotate around the z-axis, resulting in a y-component of the nuclear magnetic field Byn; (d) under the torque of magnetic field Byn on Rb electron spins, P^e rotates and projects onto the x-axis. Then, the x-component Pxe is detected by the linearly polarized probe light.